<HTML>
<BODY BGCOLOR="white">
<PRE>
<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    package org.apache.commons.math3.linear;<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>    import org.apache.commons.math3.exception.DimensionMismatchException;<a name="line.20"></a>
<FONT color="green">021</FONT>    <a name="line.21"></a>
<FONT color="green">022</FONT>    /**<a name="line.22"></a>
<FONT color="green">023</FONT>     * This class defines a linear operator operating on real ({@code double})<a name="line.23"></a>
<FONT color="green">024</FONT>     * vector spaces. No direct access to the coefficients of the underlying matrix<a name="line.24"></a>
<FONT color="green">025</FONT>     * is provided.<a name="line.25"></a>
<FONT color="green">026</FONT>     *<a name="line.26"></a>
<FONT color="green">027</FONT>     * The motivation for such an interface is well stated by<a name="line.27"></a>
<FONT color="green">028</FONT>     * &lt;a href="#BARR1994"&gt;Barrett et al. (1994)&lt;/a&gt;:<a name="line.28"></a>
<FONT color="green">029</FONT>     * &lt;blockquote&gt;<a name="line.29"></a>
<FONT color="green">030</FONT>     *  We restrict ourselves to iterative methods, which work by repeatedly<a name="line.30"></a>
<FONT color="green">031</FONT>     *  improving an approximate solution until it is accurate enough. These<a name="line.31"></a>
<FONT color="green">032</FONT>     *  methods access the coefficient matrix A of the linear system only via the<a name="line.32"></a>
<FONT color="green">033</FONT>     *  matrix-vector product y = A &amp;middot; x<a name="line.33"></a>
<FONT color="green">034</FONT>     *  (and perhaps z = A&lt;sup&gt;T&lt;/sup&gt; &amp;middot; x). Thus the user need only<a name="line.34"></a>
<FONT color="green">035</FONT>     *  supply a subroutine for computing y (and perhaps z) given x, which permits<a name="line.35"></a>
<FONT color="green">036</FONT>     *  full exploitation of the sparsity or other special structure of A.<a name="line.36"></a>
<FONT color="green">037</FONT>     * &lt;/blockquote&gt;<a name="line.37"></a>
<FONT color="green">038</FONT>     * &lt;br/&gt;<a name="line.38"></a>
<FONT color="green">039</FONT>     *<a name="line.39"></a>
<FONT color="green">040</FONT>     * &lt;dl&gt;<a name="line.40"></a>
<FONT color="green">041</FONT>     *  &lt;dt&gt;&lt;a name="BARR1994"&gt;Barret et al. (1994)&lt;/a&gt;&lt;/dt&gt;<a name="line.41"></a>
<FONT color="green">042</FONT>     *  &lt;dd&gt;<a name="line.42"></a>
<FONT color="green">043</FONT>     *   R. Barrett, M. Berry, T. F. Chan, J. Demmel, J. M. Donato, J. Dongarra,<a name="line.43"></a>
<FONT color="green">044</FONT>     *   V. Eijkhout, R. Pozo, C. Romine and H. Van der Vorst,<a name="line.44"></a>
<FONT color="green">045</FONT>     *   &lt;em&gt;Templates for the Solution of Linear Systems: Building Blocks for<a name="line.45"></a>
<FONT color="green">046</FONT>     *   Iterative Methods&lt;/em&gt;, SIAM<a name="line.46"></a>
<FONT color="green">047</FONT>     *  &lt;/dd&gt;<a name="line.47"></a>
<FONT color="green">048</FONT>     * &lt;/dl&gt;<a name="line.48"></a>
<FONT color="green">049</FONT>     *<a name="line.49"></a>
<FONT color="green">050</FONT>     * @version $Id: RealLinearOperator.java 1416643 2012-12-03 19:37:14Z tn $<a name="line.50"></a>
<FONT color="green">051</FONT>     * @since 3.0<a name="line.51"></a>
<FONT color="green">052</FONT>     */<a name="line.52"></a>
<FONT color="green">053</FONT>    public abstract class RealLinearOperator {<a name="line.53"></a>
<FONT color="green">054</FONT>        /**<a name="line.54"></a>
<FONT color="green">055</FONT>         * Returns the dimension of the codomain of this operator.<a name="line.55"></a>
<FONT color="green">056</FONT>         *<a name="line.56"></a>
<FONT color="green">057</FONT>         * @return the number of rows of the underlying matrix<a name="line.57"></a>
<FONT color="green">058</FONT>         */<a name="line.58"></a>
<FONT color="green">059</FONT>        public abstract int getRowDimension();<a name="line.59"></a>
<FONT color="green">060</FONT>    <a name="line.60"></a>
<FONT color="green">061</FONT>        /**<a name="line.61"></a>
<FONT color="green">062</FONT>         * Returns the dimension of the domain of this operator.<a name="line.62"></a>
<FONT color="green">063</FONT>         *<a name="line.63"></a>
<FONT color="green">064</FONT>         * @return the number of columns of the underlying matrix<a name="line.64"></a>
<FONT color="green">065</FONT>         */<a name="line.65"></a>
<FONT color="green">066</FONT>        public abstract int getColumnDimension();<a name="line.66"></a>
<FONT color="green">067</FONT>    <a name="line.67"></a>
<FONT color="green">068</FONT>        /**<a name="line.68"></a>
<FONT color="green">069</FONT>         * Returns the result of multiplying {@code this} by the vector {@code x}.<a name="line.69"></a>
<FONT color="green">070</FONT>         *<a name="line.70"></a>
<FONT color="green">071</FONT>         * @param x the vector to operate on<a name="line.71"></a>
<FONT color="green">072</FONT>         * @return the product of {@code this} instance with {@code x}<a name="line.72"></a>
<FONT color="green">073</FONT>         * @throws DimensionMismatchException if the column dimension does not match<a name="line.73"></a>
<FONT color="green">074</FONT>         * the size of {@code x}<a name="line.74"></a>
<FONT color="green">075</FONT>         */<a name="line.75"></a>
<FONT color="green">076</FONT>        public abstract RealVector operate(final RealVector x)<a name="line.76"></a>
<FONT color="green">077</FONT>            throws DimensionMismatchException;<a name="line.77"></a>
<FONT color="green">078</FONT>    <a name="line.78"></a>
<FONT color="green">079</FONT>        /**<a name="line.79"></a>
<FONT color="green">080</FONT>         * Returns the result of multiplying the transpose of {@code this} operator<a name="line.80"></a>
<FONT color="green">081</FONT>         * by the vector {@code x} (optional operation). The default implementation<a name="line.81"></a>
<FONT color="green">082</FONT>         * throws an {@link UnsupportedOperationException}. Users overriding this<a name="line.82"></a>
<FONT color="green">083</FONT>         * method must also override {@link #isTransposable()}.<a name="line.83"></a>
<FONT color="green">084</FONT>         *<a name="line.84"></a>
<FONT color="green">085</FONT>         * @param x the vector to operate on<a name="line.85"></a>
<FONT color="green">086</FONT>         * @return the product of the transpose of {@code this} instance with<a name="line.86"></a>
<FONT color="green">087</FONT>         * {@code x}<a name="line.87"></a>
<FONT color="green">088</FONT>         * @throws org.apache.commons.math3.exception.DimensionMismatchException<a name="line.88"></a>
<FONT color="green">089</FONT>         * if the row dimension does not match the size of {@code x}<a name="line.89"></a>
<FONT color="green">090</FONT>         * @throws UnsupportedOperationException if this operation is not supported<a name="line.90"></a>
<FONT color="green">091</FONT>         * by {@code this} operator<a name="line.91"></a>
<FONT color="green">092</FONT>         */<a name="line.92"></a>
<FONT color="green">093</FONT>        public RealVector operateTranspose(final RealVector x)<a name="line.93"></a>
<FONT color="green">094</FONT>            throws DimensionMismatchException, UnsupportedOperationException {<a name="line.94"></a>
<FONT color="green">095</FONT>            throw new UnsupportedOperationException();<a name="line.95"></a>
<FONT color="green">096</FONT>        }<a name="line.96"></a>
<FONT color="green">097</FONT>    <a name="line.97"></a>
<FONT color="green">098</FONT>        /**<a name="line.98"></a>
<FONT color="green">099</FONT>         * Returns {@code true} if this operator supports<a name="line.99"></a>
<FONT color="green">100</FONT>         * {@link #operateTranspose(RealVector)}. If {@code true} is returned,<a name="line.100"></a>
<FONT color="green">101</FONT>         * {@link #operateTranspose(RealVector)} should not throw<a name="line.101"></a>
<FONT color="green">102</FONT>         * {@code UnsupportedOperationException}. The default implementation returns<a name="line.102"></a>
<FONT color="green">103</FONT>         * {@code false}.<a name="line.103"></a>
<FONT color="green">104</FONT>         *<a name="line.104"></a>
<FONT color="green">105</FONT>         * @return {@code false}<a name="line.105"></a>
<FONT color="green">106</FONT>         */<a name="line.106"></a>
<FONT color="green">107</FONT>        public boolean isTransposable() {<a name="line.107"></a>
<FONT color="green">108</FONT>            return false;<a name="line.108"></a>
<FONT color="green">109</FONT>        }<a name="line.109"></a>
<FONT color="green">110</FONT>    }<a name="line.110"></a>




























































</PRE>
</BODY>
</HTML>
